The presented study deals with the method of a computer analysis of writing. The author proposes an example of the application of computer image analysis for the purpose of deciphering writing upon the example of an analysis of an inscription over the gate in Bierzgłowo Castle, executed in b u rn t ceramic. The studies were based on images obtained by means of high definition CDD cameras. Digital analysis and processing made it possible to correct perspective abbreviations and to make patterns of the letters, followed by their comparison by a graphic programme or one intended for this purpose (e. g. Pluskwa 5.0). Such an approach also facilitates computer supplementation of the missing elements of the letters, preceded by comparative analysis. Upon the basis of the presented examples of a computer analysis of writing it was found that: — the possibilities of an analysis of letters with the aid of computer studies render feasible the elimination of chance in deciphering letters, and facilitate an unambiguous interpretation of inscriptions; — systematic computer handling of analyses of this type aims at creating a lettering base, making it easier to interpre t other inscriptions from the same historical period, etc. — digital archives of analyses results (e. g. CD-ROM) comprise a base for classical studies, publications or the continuation of research, without the necessity of taking successive photographs, which often prove harmful to the state of the objectas preservation (destruction of pigments, paper and fabric due to radiation).